Question

What would happen if I touch the top of the positively charged electroscope with a negatively charged rod? How do you explain what would happen?

A. The foils will come together because electrons move onto the leaves from the rod to cancel out the positive charge.
B. The foils will come together because protons move onto the rod from the leaves.
C. The foils will seperate more.

Answer 1

Touching a positively charged electroscope with a negatively charged rod causes electrons to transfer to the electroscope, neutralizing its positive charge and causing the foils to come together.

Step-by-step explanation:

If you touch the top of a positively charged electroscope with a negatively charged rod, the foils will come together because electrons move from the rod onto the leaves to cancel out the positive charge. Protons do not move in this situation; it's the electrons that are mobile in metals and are transferred to balance out the positive charge of the electroscope.

When the negative rod touches the electroscope, electrons will flow from the rod into the electroscope until the excess positive charge that was initially present is neutralized. As a result, the leaves, which were previously separated due to a net positive charge (like charges repel), will now come together because there will be less repulsion once the electroscope becomes more neutral or slightly negatively charged.